1. Technical Field
The present invention relates to an input device connected to or installed on an electronic device such as a computer or mobile phone, more particularly to a keyboard having light emitting function.
2. Description of Related Art
A keyboard installed on a conventional notebook computer or desktop computer is not equipped with a light emitting function, but with the technology development of the backlight module, some manufacturers have installed a light emitting device in a keyboard, thereby the keyboard is not only provided with an illumination effect, but also provided with a decorative function.
A conventional light-emitting keyboard comprises a key module and a backlight module. The key module comprises a base board on which at least one light-transmissive key capable of up/down moving relative to the base board is installed; the backlight module is installed below the key module and fastened with the key module. Accordingly, the backlight module can provide light from the bottom of the key module, and the light can penetrate the light-transmissive key for enabling the key to generate the light emitting effect. Because the market trend of electronic products is to be smaller and thinner, thus at present, beside providing the light emitting effect to the light-emitting keyboard, the requirement of reducing the thickness of keyboard also has to be considered.
The conventional art is to provide a thin standard keyboard, the structure thereof comprises an electric circuit substrate installed on a base board and a transparent board, the transparent board is provided with a light guide plate, and a light source is electrically connected to the electric circuit substrate. The light source can project light from a lateral side of the light guide plate for entering the light guide plate; an outer membrane having a plurality of key caps is installed on the outermost layer of the keyboard. When one of the key caps of the outer membrane is pressed, the key cap presses on a membrane switch formed on the electric circuit substrate through a corresponding elastic element, so a key signal is outputted. Wherein the base board and the electric circuit substrate has a reflection board, so a part of the light emitted by the light source can be reflected by the base board for passing through the electric circuit substrate then penetrating the light guide plate and the outer membrane, thereby presenting a light emitting effect.
However, the light permeability of the electric circuit substrate is poor, and the reflected light has to pass through various mediums then eventually be emitted out from the outer membrane, the light quantity reflecting out from the outer membrane is greatly reduced, thereby lowering the light emitting efficiency of the whole keyboard.
Moreover, the structure of installing the elastic element below the key module is complicated, so the assembly cost is affected. After the elastic element is installed in the key module, the elastic element may be shaken or displaced due to poor positioning and dislocation of the elastic element may occur.